The following abbreviations and terms are herewith defined, at least some of which are referred to within the following description of the present disclosure.    3GPP 3rd-Generation Partnership Project    AB Access Burst    AGCH Access Grant Channel    ASIC Application Specific Integrated Circuit    BCCH Broadcast Control Channel    BLER Block Error Ratio    BSC Base Station Controller    BSS Base Station Subsystem    CC Coverage Class    CCCH Common Control Channel    CIoT Cellular Internet of Things    CN Core Network    DL Downlink    DSP Digital Signal Processor    eDRX Extended Discontinuous Receive    EC-GSM Extended Coverage-Global System for Mobile Communications    EDGE Enhanced Data rates for GSM Evolution    EGPRS Enhanced General Packet Radio Service    eNB evolved Node B    E-UTRA Evolved Universal Terrestrial Radio Access    FCCH Frequency Correction Channel    GSM Global System for Mobile Communications    GERAN GSM/EDGE Radio Access Network    HARQ Hybrid Automatic Repeat Request    IE Information Element    IMSI International Mobile Subscriber Identity    IoT Internet of Things    LLC Logical Link Control    MCL Maximum Coupling Loss    MME Mobile Management Entity    MTC Machine Type Communications    NAS Non-Access Stratum    NB Normal Burst    LTE Long-Term Evolution    PACCH Packet Associated Control Channel    PDN Packet Data Network    PDTCH Packet Data Traffic Channels    PDU Protocol Data Unit    RACH Random Access Channel    RAN Radio Access Network    RAT Radio Access Technology    RAU Routing Area Update    RCC Radio Coverage Category    RLC Radio Link Control    RNC Radio Network Controller    RRC Radio Resource Control    SCH Synchronization Channel    SGSN Serving GPRS Support Node    SI System Information    TA Timing Advance    TLLI Temporary Logical Link Identifier    TS Timeslot    UE User Equipment    UL Uplink    UMTS Universal Mobile Telecommunications System    WCDMA Wideband Code Division Multiple Access    WiMAX Worldwide Interoperability for Microwave Access
The anticipated ubiquitous deployment of wireless devices used for what is known as Machine-Type-Communication (MTC) will result in wireless devices being placed outside the typical radio coverage of the existing radio networks, e.g., in basements and similar locations. One way to improve the radio coverage is by expanding the radio access network infrastructure, such as by adding additional Radio Base Station (RBS) equipment. This, however, may very quickly result in an unreasonable investment effort and may not be acceptable to operators.
An alternative approach to adding additional equipment is to keep the existing radio access network infrastructure unchanged but instead improve the radio coverage through novel radio transmission and reception techniques as well as new Radio Resource Management algorithms. The latter approach is currently being discussed in the wireless industry and is a subject for a standardization effort, for example, in the 3rd-Generation Partnership Project (3GPP) as described in the 3GPP TR 36.824 V11.0.0 Technical Report, entitled “Evolved Universal Terrestrial Radio Access (E-UTRA); LTE coverage enhancements” and the 3GPP TSG-GERAN Meeting #62 Work Item Description GP-140421, entitled “New Study Item on Cellular System Support for Ultra Low Complexity and Low Throughput Internet of Things.” The contents of these two documents are hereby incorporated herein by reference for all purposes.
While there are many techniques that can be used to enhance the radio coverage, one technique is to enhance the radio coverage through the use of repeated transmissions. The repeated transmissions technique is currently being considered in the context of the related standardization work in 3GPP TSG RAN, as described in the above-referenced 3GPP TR 36.824 V11.0.0 Technical Report, entitled “Evolved Universal Terrestrial Radio Access (E-UTRA); LTE coverage enhancements” as well as in 3GPP TSG GERAN as described in the 3GPP TR 45.820 V1.3.0 Technical Report, entitled “Cellular System Support for Ultra Low Complexity and Low Throughput Internet of Things”.
A problem seen with the existing solutions associated with the repeated transmissions technique described in the above-referenced Technical Reports is that neither the wireless device nor the network, in this case, the Radio Access Network (RAN) node responsible for the repeated transmissions (e.g., the evolved Node B (eNB) in Long Term Evolution (LTE), the Radio Network Controller (RNC) in 3G, or the Base Station Controller (BSC) in 2G), is aware of the Radio Coverage Category (RCC) applicable when starting up a new uplink or downlink data transmission for a wireless device. This may, in a large degree, result in either too few or too many repeated transmissions during the initial phase of the data transmissions with the wireless device (e.g., a period of time during which wireless device specific RCC information is not known by the RAN node). For example, too few repeated transmissions may be initially applied to the transmissions, resulting in a failed data transmission, due to an erroneous initial estimate in the number of repeated transmissions needed. This may then be followed by another set of repeated transmissions based on a better understanding of the needed number of repeated transmissions (e.g., derived from the failed data transmission) but still resulting in inefficient usage of the scarce radio resources. Alternatively, too many repeated transmissions may be initially applied to the transmissions, resulting in the inefficient usage of the scarce radio resources, adding interference to the network, and consuming too much energy, etcetera.
Given that a large portion of the applications associated with MTC (including Internet of Things (IoT)) will be predominantly used for transfer of small amounts of a data (e.g., electricity meter data, temperature sensor data, etc.), an improved mechanism for accurately determining the number of needed repeated transmissions to and/or from a wireless device would be a very valuable if not a critical requirement to satisfy during the initial phase of downlink or uplink data transmission between the RAN node and the wireless device. This need and other needs are addressed by the present disclosure.